Plant protection agents

ABSTRACT

The present invention relates to a microbicide composition for plants, containing at least two active ingredient components in an amount producing synergistic activity, together with an appropriate filler, wherein component I is the compound 2-[α-{[(α-methyl-3-trifluoromethyl-benzyl)imino]-oxy}-o-tolyl]-glyoxylic acid-methylester-O-methyloxime, and component II is a compound selected from the group consisting of IIA) 5,7-dichloro-4-(4-fluorophenoxy)quinoline (“Quinoxyfen”); IIB) 4-cyclopropyl-6-methyl-N-phenyl-2-pyrimidinamine (“Cyprodinil”); IIC) benzo(1,2,3) thiadiazole-7-carbothio-acid-5-methylester (“Acibenzolar-S-methyl”); IID) 3-anilino-5-methyl-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione (“Famoxadone”); IIE) 8-(1,1-dimethylethyl)-N-ethyl-N-propyl-1,4-dioxaspiro[4.5]decane-2-methanamine (“Spiroxamin”); IIF) 4-(2, 2-difluoro-1,3-benzodioxol-4-yl)pyrrole-3-carbonitrile (“Fludioxonil”); IIG) 4-(2,3-dichlorophenyl)pyrrole-3-carbonitrile (“Fenpiclonil”); IIH) 1-methyl-cyclohexanecarboxylic acid-(2,3-dichloro-4-hydroxy-phenyl)-amide (“Fenhexamid”); IIJ) 2-{2-[6-(2-cyano-phenoxy)-pyrimidin-4-yloxy]-phenyl}-3-methoxy-acrylic acid methyl ester (“Azoxystrobin”); and IIK) Methoximino-(2-o-tolyloxymethyl-phenyl)-acetic acid methyl ester (“Kresoxim-methyl”); or respectively one of the salts or metal complexes of components I and II.

The present invention relates to new plant-protecting active ingredientmixtures having synergistically increased activity, containing at leasttwo active ingredient components, and a process for the application ofsuch mixtures in plant protection, especially in the control andprevention of disease outbreaks.

Component I is the compound

2-[α-{[(α-methyl-3-trifluoromethyl-benzyl)imino]-oxy}-o-tolyl]glyoxylicacid-methylester-O-methyloxime, (EP-A-460,575); and

component II is a compound selected from the group

IIA) 5,7-dichloro-4-(4-fluorophenoxy)quinoline (“Quinoxyfen”),(EP-A-326,330);

IIB) 4-cyclopropyl-6-methyl-N-phenyl-2-pyrimidinamine (“Cyprodinil”)(The Pesticide Manual, 10th. edition, 1994, 109);

IIC) benzo(1,2,3)thiadiazole-7-carbothio-acid-5-methylester(“Acibenzolar-5-methyl”) (EP-A-313,512);

IID) 3-anilino-5-methyl-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione(“Famoxadone”) (EP-A-393,911);

IIE)8-(1,1-dimethylethyl)-N-ethyl-N-propyl-1,4-dioxaspiro[4,5]decane-2-methanamine(“Spiroxamin”) (EP-A-281,842);

IIF) 4-(2,2-difluoro-1,3-benzodioxol-4-yl)pyrrole-3-carbonitrile(“Fludioxonil”) (The Pesticide Manual, 10th. edition, 1994, 326);

IIG) 4-(2,3-dichlorophenyl)pyrrole-3-carbonitrile (“Fenpiclonil”) (ThePesticide Manual, 10th. edition, 1994, 302);

IIH) 1-methyl-cyclohexanecarboxylicacid-(2,3-dichloro-4-hydroxy-phenyl)-amide (“Fenhexamid”)(EP-A-379,438);

IIJ)2-{2-[6-(2-cyano-phenoxy)-pyrimidin-4-yloxy]-phenyl}-3-methoxy-acrylicacid methyl ester (“Azoxystrobin”) (EP-A-382,375);

IIK) Methoximino-(2-o-tolyloxymethyl-phenyl)-acetic acid methyl ester(“Kresoxim-methyl”) (EP-A-398,692);

or repectively one of the salts or metal complexes of components I andII.

It has now surprisingly been shown that the mixtures of components I andII according to the invention display not only additive action, butsignificant synergistically increased action in the prevention andcontrol of plant diseases.

Favourable mixture ratios of the two active ingredients are I:II=20:1 to1:20, preferably I:II=10:1 to 1:10, 6:1 to 1:6, 2:1 to 1:10 and 10:1 to1:2.

The active ingredient mixtures I+II according to the invention have veryadvantageous properties in the protection of plants against the outbreakof disease.

In addition, mixtures with compound IIc can activate the defence system,which is latent in the plant, against pathogenic microbial influencesand can thus protect the plant by immunisation.

With the present active ingredient mixtures, the microorganismsappearing on plants or plant parts (fruits, flowers, foliage, stems,tubers, roots) of different useful plants can be stopped or destroyed,whereby plant parts growing later also remain free from suchmicroorganisms. They may also be used as dressings for the treatment ofplant propagation material, especially seeds (fruits, tubers, seedgrain) and plant cuttings (e.g. rice) to provide protection from fungalinfections, and against phytopathogenic fungi appearing in the soil. Theactive ingredient mixtures according to the invention are notable fortheir especially good plant tolerance and their environmentalacceptability.

The active ingredient mixtures according to the invention are effectiveagainst the following classes of related phytopathogenic fungi:ascomycetes (e.g. Venturia, Podosphaera, Erysiphe, Monilinia,Mycosphaerella, Uncinula); basidiomycetes (e.g. the genus Hemileia,Rhizoctonia, Puccinia); Fungi imperfecti (e.g. Botrytis,Helminthosporium, Rhynchosporum, Fusarium, Septoria, Cercospora,Alternaria, Pyricularia and in particular Pseudocercosporellaherpotrichoides); oomycetes (e.g. Phytophthora, Peronospora, Bremia,Pythium, Plasmopara).

Target crops for the indicated fields disclosed herein are, within thecontext of this invention, e.g. the following species of plants: cereals(wheat, barley, rye, oats, rice, sorghum and the like); beets: (sugarbeet and fodder beet); pip, stone and berry fruit: (apples, pears,plums, peaches, almonds, cherries, strawberries, raspberries andblackberries); leguminous plants: (beans, lentils, peas, soybeans); oilplants: (rape, mustard, poppy, olives, sunflowers, coconut, castor oilplant, cacao, peanut); cucumber plants (gourds, cucumbers, melons);fibre plants: (cotton, flax, hemp, jute); citrus fruits: (oranges,lemons, grapefruit, mandarins); vegetable varieties (spinach, lettuce,asparagus, cabbage varieties, carrots, onions, tomatoes, potatoes,peppers); Lauraceae: (avocado, cinnamon, camphor) or plants such asmaize, tobacco, nuts, coffee, sugar cane, tea, grapevines, hops, bananaand natural rubber plants, as well as ornamental plants (flowers,shrubs, deciduous trees and coniferous trees such as conifers). This isnot intended to be a limiting list of plants.

The active ingredient mixtures according to the invention are especiallyadvantageous for the following applications:

I+IIA: for cereals and vines;

I+IIB: for cereals, particularly wheat and barley, also for vines,vegetables and fruit;

I+IIC: for cereals;

I+IID: for vines;

I+IIE: for cereals;

I+IIF: for cereals, particularly wheat and barley, also for vines andvegetables;

I+IIG: for treatment of seeds;

I+IIH: for vegetables and vines;

I+IIJ: for cereals and vines;

I+IIK: for cereals, particularly for wheat and barley.

The active ingredient mixtures of formulae I and II are normallyemployed in the form of compositions. The active ingredients of formulaeI and II may be applied to the area or plants to be treated eithersimultaneously or in succession on the same day, together with furtheroptional fillers, surfactants or other application-enhancing additiveswhich are customary in formulation techniques.

Appropriate fillers and additives may be solid or liquid, and correspondto the substances which are efficient in formulation techniques, e.g.natural or regenerated mineral substances, solvents, dispersants,wetting agents, adhesion agents, thickeners, binding agents orfertilisers.

A preferred method of applying an active ingredient mixture containingat least one of each of these active ingredients I and II is applicationto the parts of the plant above ground, especially the leaf system (leafapplication). The number of applications and application rate depend onthe biological and climatic living conditions of the instigator.However, the active ingredients may also reach the plant through theroot system (systemic action) via the soil or the water, whereby theplant site is drenched with a liquid formulation (e.g. in ricecultivation) or the substances are incorporated into the soil in solidform, e.g. in the form of granules (soil application). The compounds offormulae I and II may also be applied to seed grain in a seed treatment(coating), whereby the tubers or grains are either immersed insuccession with a liquid formulation of each active ingredient, or arecoated with an already combined, wet or dry formulation. In addition, inparticular cases, further types of plant application are possible, e.g.the targeted treatment of buds or syncarpy. Here, the compounds of thecombination are used in unchanged form or preferably together withexcipients which are usual in formulation techniques, and they areprocessed in known manner e.g. into emulsion concentrates, coatablepastes, directly sprayable or diluable solutions, diluted emulsions,wettable powders, soluble powders, dusts, granules, or by encapsulationinto, for example, polymeric substances. The application methods, suchas spraying, misting, dusting, dispersing, coating or drenching, areselected according to the targeted alms and the given conditions, in thesame way as for selection of the type of agent. Favourable applicationrates for the active ingredient mixture are in general 50 g to 2 kgactive substance per ha, especially 100 g to 700 g active substance perha, most preferably 75 g to 450 g active substance per ha. For thetreatment of seeds, the application rates are 0.5 g-600 g, preferably 5g-80 g active substance per 100 kg seeds.

The formulations are produced in known manner, e.g. by intimately mixingand/or grinding the active ingredients with diluting agents, e.g.solvents, solid fillers, and optionally surface-active compounds(surfactants).

The solvents in question may be: aromatic hydrocarbons, preferablyfractions C₈ to C₁₂, such as xylene mixtures or substitutednaphthalenes, phthalic acid esters such as dibutyl or dioctyl phthalate,aliphatic hydrocarbons such as cyclohexane or paraffins, alcohols andglycols, as well as the ethers and esters thereof, such as ethanol,ethylene glycol, ethylene glycol monomethyl ether or monoethyl ether,ketones such as cyclohexanone, strongly polar solvents such asN-methyl-2-pyrrolidone, dimethyl sulphoxide or dimethyl formamide, aswell as optionally epoxidated vegetable oils such as epoxidated coconutoil or soybean oil; or water.

The solid fillers, e.g. for dusting agents and dispersible powders, arenormally natural mineral powder, such as calcitol, talcum, kaolin,montmorillonite or attapulgite. To improve the physical properties,highly disperse silicic acid or highly disperse, absorbent polymerisatesmay also be added. The granulated, adsorptive granulate fillers may beporous types such as pumice stone, brick fragments, sepiolite orbentonite, and non-sorptive fillers are e.g. calcitol or sand.Furthermore, a number of pregranulated materials of inorganic or organicnature may also be used, especially dolomite or pulverised plantresidues.

Depending on the type of active ingredients of formulae I and II to beformulated, the surface-active compounds may be non-ionic, cationicand/or anionic surfactants with good emulsifying, dispersing and wettingproperties. By surfactants are also understood surfactant mixtures.

Especially advantageous, application-enhancing admixtures are alsonatural or synthetic phospholipids from the series cephalins andlecithins, e.g. phosphatidylethanolamine, phosphatidylserine,phosphatidylglycerol, lysollecithin.

The agrochemical compositions normally contain 0.1 to 99%, especially0.1 to 95% active ingredients of formulae I and II, 99.9 to 1%,especially 99.9 to 5% of a solid or liquid additive and 0 to 25%,especially 0.1 to 25% of a surfactant.

While concentrated formulations are preferred as commercial products,the final user normally uses diluted formulations.

The following examples serve to illustrate the invention, whereby“active ingredient” indicates a mixture of compound I and compound II ina certain mixture ratio.

FORMULATION EXAMPLES

Wettable powder a) b) c) active ingredient [I:II = 1:3(a), 1:2(b),1:1(c)] 25%  50% 75% Na ligninsulphonate 5%  5% — Na laurylsulphate 3% — 5% Na diisobutylnaphthalenesulphonate —  6% 10%octylphenol-polyethylene-glycol-ether —  2% — (7-8 mols ethylene oxide)highly disperse silicic acid 5% 10% 10% kaolin 62%  27% —

The active ingredient is mixed well with the additives and groundthoroughly in an appropriate mill. Spray powders are obtained, which canbe diluted with water to form suspensions of any desired concentration.Emulsifiable concentrate active ingredient (I:II = 1:6) 10% octylphenolpolyethylene glycol ether 3% (4-5 mols ethylene oxide) Cadodecyl-benzene-sulphonate 3% castor oil polyglycol ether (35 molsethylene oxide) 4% cyclohexanone 30% xylene mixture 50%

Emulsions of any desired dilution may be produced from this concentrateby diluting it with water, and they can be used in plant protection.Coated granule active ingredient (I:II = 1:10) 8% polyethylene glycol(molecular weight 200) 3% kaolin 89%

The finely ground active ingredient is applied evenly to the kaolinwhich is moistened with polyethylene glycol, in a mixer. In this way,dust-free coated granules are obtained.

BIOLOGICAL EXAMPLES

A synergistic effect is present if the activity of the active ingredientcombination is greater than the sum of activities of the individualcomponents.

The activity E to be expected for a given active ingredient combinationobeys the so-called COLBY formula and may be calculated as follows(COLBY, S. R. “Calculating synergistic and antagonistic responses ofherbicide combination”. Weeds, Vol. 15, pages 20-22; 1967):

ppm=milligrams active ingredient (=ai) per litre spray mixture

X=% activity from active ingredient I during application of p ppm ofactive Ingredient

Y=% activity from active ingredient II during application of q ppm ofactive ingredient

The expected (additive) activity of active ingredients I+II duringapplication of p+p ppm active ingredient is, according to Colby$E = {X + Y - \frac{X \cdot Y}{100}}$

If the activity actually observed (O) is greater than the expectedactivity (E), then the combination is super-additive in its activity,i.e. there is a synergistic effect (SF=synergie factor).

B-1 Activity Against Puccinia recondita on Wheat

a) Residual Protective Activity

Wheat plants are sprayed until dripping wet, 6 days after sowing, withan aqueous spray mixture prepared from wettable powder of the activeingredient mixture, and are infected 24 hours later with a uredosporesuspension of the fungus. After an incubation period of 48 hours(conditions: 95 to 100% relative atmospheric humidity at 20° C.), theplants are placed in a greenhouse at 22° C. 12 days after infection, thefungal attack is evaluated.

b) Systemic Activity

5 days after sowing, an aqueous spray mixture prepared from wettablepowder of the active ingredient mixture is poured onto wheat plants.Care is taken that the spray mixture does not come into contact with theparts of the plants that are above ground. 48 hours later, the plantsare infected with a uredospore suspension of the fungus. After anincubation period of 48 hours (conditions: 95 to 100% relativeatmospheric humidity at 20° C.), the plants are placed in a greenhouseat 22° C. 12 days after infection, the fungal attack is evaluated.

Active ingredient mixtures comprising components IIB and IIC inparticular demonstrate good synergistic activity.

Example B-2 Activity Against Plasmopara viticola on Vines

Vine seedlings at the 4 to 5 leaf stage are sprayed until dripping wetwith an aqueous spray mixture prepared from wettable powder of theactive Ingredient mixture, and are infected 24 hours later with asporangia suspension of the fungus. The fungal attack is evaluated 6days after infection, during which period the conditions of 95 to 100%relative atmospheric humidity and a temperature of 20° C. aremaintained.

Active ingredient mixtures comprising components IIB, IID and IIA inparticular demonstrate good synergistic activity.

Example B-3 Activity Against Erysiphe graminis on Barley

a) Residual Protective Activity

Barley plants of approximately 8 cm height are sprayed until drippingwet with an aqueous spray mixture prepared from wettable powder of theactive ingredient mixture, and 3 to 4 hours later are dusted withconidia of the fungus. The Infected plants are placed in a greenhouse at22° C. 12 days after infection, the fungal attack is evaluated.

b) Systemic Activity

An aqueous spray mixture prepared from wettable powder of the activeingredient mixture is poured onto barley plants of approximately 8 cmheight. Care is taken that the spray mixture does not come into contactwith the parts of the plants that are above ground. 48 hours later, theplants are dusted with conidia of the fungus. The infected plants areplaced in a greenhouse at 22° C. 12 days after infection, the fungalattack is evaluated.

Active ingredient mixtures comprising components IIA, IID and IIE inparticular demonstrate good synergistic activity. TABLE 1 Activeingredient IIA = Quinoxyfen active active ingredient Test ingredient IIIA ratio % activity % activity SF No. mg/litre mg/litre I:II found Ocalculated E O/E 0 — — 0 (control) 1 0.1 — 6 2 1.0 — 30 3 — 0.1 4 4 —0.5 6 5 — 1.0 8 6 — 10.0 21 7 0.1 0.1 1:1  26 10 2.6 8 0.1 0.5 1:5  3012 2.5 9 0.1 1.0 1:10 21 14 1.5 10 1.0 10.0 1:10 75 45 1.7

Example B-4 Activity Against Phytophthora infestans on Tomatoes

a) Curative Activity

Tomato plants of the variety “red gnome” are sprayed with a zoosporesuspension of the fungus after cultivating for three weeks, andincubated in a cabin at 18 to 20° C. and under saturated atmospherichumidity. The humidity is stopped after 24 hours. After drying off theplants, they are sprayed with a mixture which contains the activesubstances formulated as a wettable powder. When the spray coating hasdried on, the plants are again placed in the moist cabin for 4 days. Thenumber and size of typical leaf spots which have appeared after thisperiod are the criterion for evaluating the efficacy of the testedsubstances.

b) Preventive Systemic Activity

The active substances formulated as wettable powders are applied to thesurface of the soil of three week old tomato plants of the variety “redgnome” which have been potted into single pots. After leaving for threedays, the undersides of the leaves of the plants are sprayed with azoospore suspension of Phytophthora infestans. They are then kept for 5days in a sprayed cabin at 18 to 20° C. and under saturated atmospherichumidity. After this period, typical leaf spots appear. The number andsize thereof serve to evaluate the efficacy of the tested substances.

Active ingredient mixtures comprising components IIB and IIC inparticular demonstrate good synergistic activity.

Example B-5 Activity against Botrytis cinerea on Apple Fruits, ResidualProtective Action

Artificially damaged apples are treated by applying a spray mixture tothe wound sites in drops. The treated fruits are then inoculated with aspore suspension of the fungus and incubated for one week at highatmospheric humidity and ca. 20° C. The fungicide action of the testsubstance is deduced from the number of wound sites that have started torot.

Active ingredient mixtures comprising components IIB and IIC inparticular demonstrate good synergistic activity.

Example B-6 Activity Against Fusarium nivale on Rye (Seed Treatment)

Rye of the variety “Tetrahell” which is naturally infected with Fusariumnivale is dressed with the fungicide to be tested on a mixing roller,whereby the following concentrations are used: 20 or 6 ppm AS (based onthe weight of the seeds).

The infected and treated rye is sown in the open in October with a seeddrilling machine on plots of 3 m length and 6 seed rows. 3 repeats perconcentration. Up to evaluation of the attack, the test plantation iscultivated under normal field conditions (preferably in a region with aclosed snow cover during the winter months).

To evaluate the phytotoxicity, an appraisal is made of the seedemergence in the autumn and an appraisal is made in spring of the cropdensity/number of plants.

To determine the active ingredient activity, the percentage of plantsattacked by Fusarium is counted in spring, directly after the snow hasthawed. The active ingredient mixtures demonstrate good synergisticactivity.

1-4. (canceled)
 5. A microbicide composition for plants, containing atleast two active ingredient components in amounts producing synergisticactivity, optionally together with one or more fillers, surfactants,and/or other additives, wherein component I is2-[α-{[(α-methyl-3-trifluoromethyl-benzyl)imino]-oxy}-o-tolyl]-glyoxylicacid-methylester-O-methyloxime, and component II is a compound selectedfrom the group consisting of IIC)benzo(1,2,3)thiadiazole-7-carbothio-acid-5-methylester(“acibenzolar-5-methyl”); IID)3-anilino-5-methyl-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione(“famoxadone”); IIJ)2-{2-[6-(2-cyano-phenoxy)-pyrimidin-4-yloxy]-phenyl}-3-methoxy-acrylicacid methyl ester (“azoxystrobin”); and IIK)methoximino-(2-o-tolyloxymethyl-phenyl)-acetic acid methyl ester(“kresoxim-methyl”); or a salt or metal complex of components I and/orII.
 6. The composition according to claim 5 wherein the weight ratio ofcomponent I to component II is 20:1 to 1:20.
 7. A method for the controlof plant diseases comprising applying a synergistically effective amountof the composition according to claim 5 to a plant site or plant locussimultaneously, in succession, or on the same day.